At 1520 Pacific time the airplane collided with hilly terrain and was substantially damaged. The Instrument rated Private pilot and passenger sustained fatal injuries. Instrument conditions prevailed at the accident site. After receiving a pop-up IFR clearance, the airplane was cleared for the instrument landing system (ILS) approach for Runway 25R and was given the current weather conditions of 600 feet overcast and three miles visibility. Shortly thereafter, controllers unsuccessfully attempted to contact the pilot. The airplane came to rest at an approximate altitude of 1467 feet msl. The ILS Runway 25R approachs glideslope intercept altitude is 2800 feet msl.